This application requests funding for an exploratory/developmental (R21) study of the prevalence of 2 common STDs, chlamydia and gonorrhea, and drug use among newly incarcerated adolescent males and females and to collect self-report measures from detained juveniles on their substance use, sexual risk behaviors, condom attitudes, and other social and psychological factors that influence vulnerability to HIV and other STDs for the purpose of testing gender-specific explanatory models of condom use or sexual risk behavior among incarcerated adolescents. Approximately 1500 juveniles (the population of detainees) will be screened for STDs and drug use in one year and at least 1000 of those juveniles will be recruited for the study. Sufficient females will be recruited to allow data analysis by gender. The positivity rate (proportion of positive tests) for STDs and drug use will be reported by race and gender. Multivariate logistic regression will be used to identify predictors of STD status. Structural equation modeling (SEM) with latent variables will be used to develop an explanatory model of condom use for incarcerated juvenile offenders. The ultimate goal of this study is to lay the foundation for development and testing of an HIV risk reduction intervention tailored to the needs of male and female juvenile offenders and applicable for youth detention settings. This application will also provide beneficial health services to juvenile offenders not currently available to them. Grant funds will be used to provide STD screening, STD treatment referral, and HIV testing and counseling to juveniles in detention.